Meanwhile, immigrant integration is one of the top themes of the political and public discourse in Germany. The article explores - based on a content and argumentation analysis of policy documents and parliamentary debates - the political party conceptions of immigrant integration and asks for changing criteria of inclusion and exclusion and the redrawing of discursive as well as legal boundaries between citizens and non-citizens in Germany. By first applying Seyla Benhabibs "paradox of democratic legitimacy" as a category of analysis and comparison of two parliamentary debates (concerning the 1990 Foreigner Law and the 2004 Immigration Law), it turns out that the formal "legitimacy quality" of arguments, in terms of justifying immigration and integration policies as balancing the interests of the national state with legitimate claims of immigrants, has decreased since Germanys self-recognition as an immigration country. Second, by exploring how the term integration is defined, used and explained by political representatives and in official documents more recently, a growing interparty consensus is visible, according to which integration is primarily related to education and employability, and corresponding competencies of individual persons. Because of obvious analogies with discourses and laws in social and labor market policies, it is finally argued that the most promising explanation of the current German integration regime places integration within a far-reaching transformation of the German welfare system toward an activation state, in which rights are increasingly made conditional on individual performances that are considered beneficial to collective goals such as the economic development of overall society.